I saw a quote on the internet:
"If someone asks me who I want to be with, I would simply say".
If I use a part of this sentence and put words like this:
"You are the one who I want to be with."
Will it be correct?
Edited the answer:
Yes, this is correct.
As you can see from the comments, some people insist on using whom instead of who and they are right from the formal English grammar point of view. However, using who in your particular sentence is acceptable and, in my opinion, this would be the choice of most English speaking people these days.
Let me point out that when I gave my answer I meant the spoken language. In (formal) writing the choice between who and whom would probably be in favour of whom.
Actually, who/whom may be simply omitted here. "You're the one I want to be with" - that's what most people would say. :)